1. Field of the Invention
The present invention relates to teaching devices and, in particular, to a teaching aid system for assisting students and users apply trigonometric lessons in real life applications.
2. Prior Art
In teaching young students, particularly those of advanced stature as early as elementary school, Applicant has found that the thirst and assimilation of classroom knowledge is enhanced by providing the opportunity to apply the lessons in ways related to daily experiences and observations.
In U.S. Pat. No. 5,732,474 issued to Cannon (1998), illustrates two dimensional nomographic device that uses the angular relationship between the moving arm and the angular scale. Two independent transparent slide indicators are mounted below the chart board one of which slides in the horizontal direction and is marked with an opaque vertical indicating line, the other of which slides in the vertical direction and is marked with an opaque horizontal line. There are no provisions in the device to actually enable the user to apply the trigonometric relationship to real time objects.
In U.S. Pat. No. 7,278,217 to Mills (2007), the aid comprises of a vertical support member and two semi-circular protractors, the protractors have same quadrant angulations preventing accurate angulations which extend beyond 180 degrees. The aid also does not allow 360 degree swivel of a simple barrel scope and angular inclination measurements, also the aid does not all allow 360 degree measurements. The aid needs setup and level adjustment, before taking measurements as it lacks angulations self alignment on any plane. It cannot self align its angulations to automatically indicate true horizontal and vertical.
The aid has a level that the user needs to refer to align to the horizontal before taking any measurements, also using the attached level increases chance of parallax errors and other inaccuracies. The aid has no resting means or supports, it may be only used as a handheld which will further the inherent inaccuracies. If the aid is used on uneven ground it can increase reading errors. The aid also highly depends on other external measurement gages such as a yard stick or tape measure for ground level or distance measurements. It is not a stand alone device and does not allow a user to learn all aspects of trigonometric ratios which involve cyclic gyrations.
In U.S. Pat. No. 3,322,340 issued to Frantland (1967) the instrument teaches the triangulations using trigonometric functions such as sine, tan and cosine but lacks the ability to engage the user to apply what he has learnt in simple manner. The invention comprises of a protractor scale and a vernier alignable therewith and operative in combination with a pair of micrometers, each having a vernier dial associated therewith and operated to indicate accurate calculations. The invention is primarily for the purpose of measuring geometrical figures as right-angle triangles, equiangular or equilateral triangles, isosceles triangles, and other polygonal figures when they can be broken down to right-angles triangles and when one side or more factor of right-angled triangle is known. The device is used as an instrument for triangulations and is not proposed to be used as a teaching aid or an educational device due to its complexity and inability to directly apply trigonometric relationships in real time.
In U.S. Pat. No. 1,955,392 issued to Shimberg (1934) the invention a trigonometric teaching device is used to demonstrate the changes in the trigonometric functions to angle changes by using a swinging member on a chart. The invention comprises of a swingable member, forming one movable side of the angle in connection with a suitable chart, properly ruled, and inscribed with a stationary line giving the other side of the angle whereby variations of the line functions corresponding to variations of an angle are illustrated on the chart. The invention uses a swinging member on a connected chart to animate the angular displacement; it does not associate it to any real time entity. The tool in its presented form lacks the application aspect altogether.
In U.S. Pat. No. 3,826,021 issued to Andrea (1974) is another two dimensional trigonometric visual demonstration tool that has a planar member having a unit circle inscribed with angulations. The planar member also includes a vertically extending, ordinate corridor, defined by the ordinate axis and scale associated shows the numerical values corresponding to secant, cosecant and other trigonometric functions. A transparent cursor member having a radius vector hairline is pivotally mounted at the origin of the unit circle. The device does not enable any application of trigonometric measurements on real time applications.
Similar U.S. Pat. No. 378,257 issued to Leschorn (1888), U.S. Pat. No. 3,359,653 issued to Redfern (1967), U.S. Pat. No. 3,556,397 issued to Anderson (1971) comprise of a pivoting arm or slide rulers attached to chart or protractor angulations. These inventions are for a student to understand the trigonometric relations in a class room and do not allow the learner to use them in real world or real world applications.
All the above invention's angular displacements need a point of reference and or a reference plane for angular displacement beyond the capability of the attached reference charts or connected planes. Also, the devices such as stated above lack the apparatus to enable them to automatically refer to true horizontal and vertical axis or plane of devices.